Muscle relaxant medicaments have the common characteristic of reducing the muscle tone, for example in muscle contractures.
Muscle contracture is a feature characterizing a number of pathologies of the locomotor apparatus, and it is one of the major factors responsible for the persistence of the painful condition related thereto. Muscle contracture also occurs in the inflammatory-rheumathic and degenerative orthopedic pathologies; when affecting an articulation, it causes, in addition to pain, a stiffening which limits the mutual mobility of the joint extremities and therefore the functionality of the part involved. Due to these reasons, there is a great interest in molecules characterized by remarkable muscle relaxant and antispastic properties.
Colchicine is known to be a pseudo-alkaloid used widely and for a very long time in therapy for the treatment of gout. Likewise widely used in therapy is of 3-demethyl-thiocolchicine glucoside, namely thiocolchicoside, as an antispastic in the inflammatory processes against skeletal muscles (Ortopedia e Traumatologia Oggi XII, n. 4, 1992). Recently, thiocolchicoside activity has been proved to be related to its interaction with strychnine-sensitive glycine receptors, therefore compounds having glycine-mimetic activity can be used in the rheumathologic-orthopedic field thanks to their muscle relaxant characteristics.